How to build a stock trials bike

I've noticed a lot of people asking questions about how to set up their bikes or what new products to get. With 6 years of riding behind me, I've tried a lot of different products and set-ups. Here's a quick guide for all you guys unsure of where to go:

*NOTE* Unless otherwise stated, I am assuming that you are trying to build up a serious trials bike where weight is an important factor. If you are thinking of building up a DJ or slalom bike to double as a trials bike, this guide ain't for you.

Frame:
If you have an old frame that you aren't sure of whether it's going to work, but you can't afford something new, don't worry. I learned trials when I was 13 on a 30lbs Specialized Hardrock. I also rode trials on my 18" GT Avalanche. Any frame can work as a trials frame, so if you are stuck with one, use it. When you break it, or you can afford something new, then it's time to worry about what to get.

Once you are looking at a new frame, you have two options:

First is to simply get a smaller mountain bike frame. Here you will have a frame that may be more versitle if you decide not to continue trials. You may also find these pretty cheaply. Mountain bike frames are easy to find and you have lots of options to choose from. You can also find stronger frames such as Konas. Things to avoid though... Do not get an overbuilt or race specific slalom frame. Bikes like a 24, or Balfa, or Intense tazer are not designed for trials. The headtube is going to be way too slack for precise movement. The bottom bracket will be too low for getting over technical terrain. Finally, most of these bikes will weigh more than they need to. Another common mistake is getting a bike that is TOO small. Yes, you want to get as low a frame as possible, but do not sacrifice lenght. As a trials bike you want your weight to be centered and you want room to move around over the bike. Too short of a bike and you will be forecd backwards (or have to compensate with way too long a stem) and you will be cramped, limiting your motion. My absolute favorite XC frame for trials was a 17" Schwinn Homegrown. It had great geometery, was nice and light, and was a good size for my 6' body.

Your final option is simply to invest in a dedicated trials frame. In general, this is the most expensive route. However, you will get serious performance advantages. Specifically the geometry will be spot on. You will have shorter chainstays for better rear wheel stability. You will have a higher bottom bracket for better clearance. You will have a steeper headtube for more precise steering. You will have low standover for better manuverability. You should also end up with a frame that is a good balance of strenght to weight. Note that a trials frame will not be unbreakable. I've even cracked my Planet X Zebdi after a years riding. That said, after chaning from my Schwinn to the Planet X, I'll never go back. The geometry advantage is too good to pass up.

Fork: Rigid vs. Suspension

Do NOT use a long travel fork for trials. You can try it if you want, but you'll hate it. If you want to go with suspesion, there are a few tips to follow. Stick with short travel. 80mm is a max. Longer travel will mess up your headtube angle and suck up way too much of your energy. And throw in some super stiff springs. Suspension on a trials bike is there to take the edge off, not to absorb every little bump. Look for a lighter fork too. I am partial to the Marzocchi Z2's or whatever is comperable now.

I prefer rigid though. You will lose absolutely no energy to the fork. A rigid fork will also keep your front end lower, which is better for technical riding and steep ups. And as long as you don't go with a Planet X knifen fork, a rigid fork will save a lot of weight too. Aluminum forks from Orange, DDG, and Brisa are good choices.

Bar/stem:

Again, you are not building a slalom frame. Don't put on a 50mm or 70mm stem. You will be too cramped and too far back on the bike for trials. Otherwise, I can only recomend that you try as many different sizes as possible and find what you like best. In general, a shorter stem is better for urban style riding. It will be easier to manual and more stable at speed. For urban riding, I use a 100mm x 15* raceface stem. For competition or more serious trials riding, I use a 120mm x 10* stem. A longer stem will help you strech out more and get your weight forward which is better for technical riding. Lower is also better for technical riding. When you are on a really steep up, the lower the front end is, the easier it is for you to get forward over the front wheel. A shorter taller stem will just send you backwards. A longer stem also gives you more leverage for spinning moves.

The bar is less important. Go with about 1-1/2" of rise and fine tune the height with your stem. And wider is better. A wider handlebar will give you more leverage for steering and spinning. I use a Easton EA70 which has a nice 27" width.

Braking:

Dun dun dun! The most important part to a trials bike. You have three choices: Maguras, Discs, or V's. If you are stuck with cantilevers, save up quick.

V's: Cheapest. Good power. Lightest. Can be mushy, which is why I ditched my XT V-brakes.

Maguras: Great feel. Good power. Little heavy, little expensive. I use a HS-33 rear brake beacuse it feels so good.

Discs: Good feel. Great power. Unaffected by water. Expensive.
Most people stick with Magura dics because Hayes are too heavy and have poor feel for trials. The louise and Marta brakes are top choices. Be careful running a disc on the rear though as most disc mounts are NOT designed for trials. My buddy has broken 3 planet x zebdi frames at the disc mount. I run a Louise up front because you can't beat the waterproofness of a disc, but I don't run one in the back because I don't want to break my frame.

Ways to make your brakes better:

Tar and other stickey stuff: ONLY WORKS WHEN DRY. Will make a hell of a lot of noise, and will make your rims ugly as hell. Works really well though. I gave up on it years ago because of...

Grinding: If done properly, this is the single greatest step towards completely locked brakes. I suck at grinding, but my friend is awesome at it. Long story short, you take a rotary disc grinder and grind perpendicular to the rim. This will work in ANY situation, dry or wet. It will eventually wear off and you will have to regrind... repeat to much and you will crack your rim. You will also have NO modulation. And it will make a lot of noise.

Trials specific pads: Monty, Plazmatic. Softer compounds to grip better. Suposedly don't last as long, but I've never worn any out. I use plazmatic pads with a smooth rear rim. Doesn't work to well in the wet, but I like my modulation for manualing. Works great dry though.

Wheels:

Rear Rim. Two words: wide and strong. I used to love the Mavic D521 rim for trials, but it was just to narrow. I kept folding my tires over. Now i use a Tioaga DH rear rim as it is 35mm wide and the same wieght as the 521. Another option is the Planet X BMF. Even wider but heavier. It's the same rim as the Alex D32, but with eyelets. I like eyelets. A wider rear rim means wider tire which means more cusion and better traction. Strenght is pretty straight forward. I use a 32 hole 3-cross lace pattern cause I wieght 190lbs. I could probably get away with a radial non drive-side lace because I am really smooth and don't use a disc. If you are light and smooth, it is something to consider. Another more drastic way to save weight is to drill holes in the rim between the spokes. ONLY consider this if you are a highly skilled rider who is very smooth and good to your bike. It will save a lot of weight, but you can taco your rim in no time flat.

Rear Hub: The faster it engages the better. I will never use anything but a Chris King. Slower hubs like shimano require a LOT more work and are very imprecise. Chris King is the fastest hub I have ever owned and their customer service is incredbile! When my hub started skipping after two years of trials, I sent it in and they completely rebuilt it with a new stainless steel driveshell, free of cost. They've done this for a lot of other riders I know too. Great product. Expensive as hell, but worth every penny.

Rear Tire: Wide, but not to heavy. Don't run a stiff, 1300 gram DH tire. Run something in the 2.3 range at around 1100 grams. You want a sidewall stiff enough to prevent pinch flats, but soft enough to give you some cusion. Slow rebound will give you better traction but will wear out faster. Rectangular, horizontally spaced knobs are best. Good options are the Maxxis High Roller, IRC Kujo, Michelin (the DH version of the Hot S), and I use a Tioga DH 2.3. It's really light for it's size, but the sidewall is not the stiffest. I never pinch-flatted on a 2.35 kujo, but I do pinch the Tioga every now and then. I run 20-30 psi depending on terrain. 35 for urban.

Front wheel. One word: weight. You're not going to be spending much time on your front wheel, so make sure it has as small of an impact on your bike as possible. Any lightweight XC rim will do. I use a Mavic X317 but may soon go to a Tioga xc so that my rims match and I have the option of runing a rim brake (X317's are disc specific). I also run a 3 cross due to the disc, but if you are light and using rim brakes, a radial lace is acceptable. For a front hub, use something light and economic. I use a DT onyx disc. Any old XC front tire will work. I have used IRC Mythos, Michelin Hot S, and now use a Tioga Extreme XC. Again, slow rebound will help. You can go wider if you want more cusion and better traction, but a 2.1 will work for most. I run about 30 psi in my front tire. 40 for urban.

Cranks: Strong and stiff. Raceface turboline LP's were the favorites, but now there are stronger alternatives. RF Northshore, Truvative Husselfelts, Middleburn Trials, and I use shimano XTR's. If you are a big, clumsy rider, Profile's are great cranks but heavy as hell. I used these for a long time before i found a deal on my XTR's. In terms of lenght, shorter is somewhat better. Basic rule is to go 5mm less than your XC cranks. I'm 6'1" but ride 170mm cranks for trials. You loose a little bit of leverage with the shorter lenght, but your pedal stroke is much smoother, increasing your balance and accuracy.

Pedals: Cage or platform. Ditch the clipless, you'll end up on your ass I promise you. Platforms are best for urban riding. Cages will give you better traction, but are not very strong.

Bashring: Depends on how many rings you run. If you are serious and are only running a small ring, a good bashing is the Holm Bros bashring. It's 1/2" thick for great stability and safely protects a 22 tooth cog while givning you plent of clearance. A lot of riders are also switching to a smaller, smooth ring to cover a 20 tooth cog. Even more clearance, less weight, and the smooth outer edge promotes smoother riding.

Shifter: Doesn't really matter. As a mechanic, I hate gripshift, but it doesn't gouge my knees like a trigger shifter. I use a Sram Attack 8.0 shifter.

R. Derailleur: Get something cheap, strong, and short cage. A mid-level shimano road derailleur or a sunrace are great choices. Don't waste money on XTR, it's just going to get beaten.

Gears: Don't waste time with 9speed. Get yourself a 7 or 8 speed road cassette with a 12 to 19 or 21 tooth range. My trials gear is a 22 front with 19 rear. I run 5 cogs on the back (minimum for US competition) with a 11-19 tooth range. Doesn't shift very well, but my trials gear works and that's all that matters to me.

I use a sachs/sram chain by preference. And I've never had a powerlink break on me.

Seat: Get something light, slim, and with a smooth back. Any sharp edges on the back of the saddle are likely to snag your clothes and can have disasterous results. I have a picture of me, mid air, with my shorts caught on my seat and my face headed right for a rock. It's a great picture, but I don't want it to happen again. I now use a Uni seat. Yes it is uncomfortable, but I don't sit down in trials, and the Uni weighs next to nothing while staying out of my way. Whatever you get, run it as low as possible for serious trials.

Excellent guide. I just would like to ad that the BEST tire combo I have ever had is 2.0" Huchinson Python Airlight front and 2.3" Tioga DH. CANNOT go wrong with that tire combo. Massive traction in the back, super light in the front.

is your name Jim? how about Paul? Me and a posse of Mods went to SF last wekeend. We rode for several hours at GG park, then went to that old army base under the GG bridge. An epic ride. if you want to get together on a weekend to do some riding, let me know. I live in Davis, and theres some spots that are halfway between us, but I don't mind heading into the city....

Are you the Kevin who comes up to Davis to pick up your girlfriend on Tuesdays, or are you the other kevin that I haven't met yet? I'm Nikolai.
Me and Justin went to Santa Cruz yesterday to ride. We were supposed to meet up with Alex and Phil, only they were two hours late, so we ended up bailing on the meeting spot minutes before they showed up. My car got "broken into". Stupid Justin left the door unlocked. But the thief luckily (for me) stole only Justins wallet, keys and frappuchinos. Maybe that will finally teach him that I don't have power locks in my car. In any case, that was a long ass drive that I don't soon want to do again.

I'm going to throw in my 2 cents and hopuflly this dosn't start a flame war. As for brakes, v-brakes are the way to go (maybe disks never tried them). Alot of frame manufaturers are finally seeing the light and saying the hell with magura specific mounts. I guess brakes are a thing of preference but quality v-brakes provide better stoping power than any set of maggies. If your starting out don't waste your money or time on a set of hydraulic rim brakes.

I guess there are two of us.
Whenever I order from Jenson, they try to guess my address from their database of previous customers. They always guess some other guy first who has the exact same name as me. Does your last name start with B? because that would be crazy.

Good guide. I have used both hs33 and v-brakes on the back. I can really recommend Avid SD7 with XT levers, red Ritchey pads and the Odyssey Linear Slic Kable. As good as HS33 and won't leak. The Deore V's come highly reommended too.